Urinary incontinence (UI) is one of the most prevalent conditions, affecting approximately 40% of women in the United States and the Western world. Stress urinary incontinence (SUI) accounts for the largest portion of these women, and is found in women of all ages, including an estimated 30-40% of women above the age of 60. Despite the common surgical use of mid-urethral slings, this procedure is still associated with a disturbing level of complications. Regenerative medicine cellular therapy approaches have therefore garnered attention for treatment of SUI. In particular, the transplantation of adipose stem cells into or adjacent to the urethral sphincter muscle show promising results and appears to be a safe alternative to traditional treatments. Efficacy of this therapy is likely dependent on both the delivery and retention of cells in the muscle but there are currently no means for assessing cellular persistence without an invasive biopsy. Celsense, Inc. focuses on developing cellular imaging agents for human health and currently has a magnetic resonance imaging (MRI) cell-tracking probe in use in an FDA-authorized Phase I clinical trial. Recently, Celsense has developed a cell- tracking probe with both MRI and near infra-red optical imaging capabilities (CS-DM-NIR). Optical imaging lacks the anatomical capabilities of MRI, but is rapid with compact imaging hardware, lending itself to remote endoscopic imaging applications, including in doctors' offices or surgical suites. These capabilities will allow rapid, facile measurement of cell delivery and persistence, allowing optimization of both the therapeutic and treatment regimen. In this project, we propose to develop a dataset to support the future clinical application of labeled stem cells through the evaluation of labeling efficiency (Aim 1) and safety (Aim 2) of CS-DM-NIR on human adipose stem cells in vitro. The labeling characteristics of CS-DM-NIR will be established to ensure adequate labeling for in vivo applications, and assess any potential impact of the label itself on cell function and viability. Aim 3 will determine the efficcy of imaging labeled adipose stem cells in vivo, and provide primary data on the effectiveness of cell delivery and retention in a rat model of SUI by both optical and MR imaging. The data generated here will support the combined efforts of the assembled research team's objective to develop an effective cell-based therapy for treating SUI. The successful development of this dual mode probe would permit a fast, highly cost-effective imaging approach through optical means, but also permit precise anatomical imaging with cell quantification when paired with MRI, criteria necessary for the assessment of cellular persistence in the treatment of SUI.